Mail loops

[Bob Bish <bobbish @ earthlink . net>]

    Is anyone else getting a huge number of bounce messages all saying "too 
many hops", "mail loop detected", etc?  I received over 500 of them in a 
50-minute period!  They started suddenly about 2 hours ago (maybe around 
5:30pm EST).
    I need to know if this is a generalized problem (perhaps a hacking or 
virus attack on the Internet as a whole) or if there's a problem on our 
server's end.

...Bob